Determining mode

[JasonMcG]

Hi

I'm having trouble determining the mode. If the sequence is 9 3 3 3 9. The mode is found to be 9. It always tends to choose the higher value that's repeated even if it's less times. Any suggestions would be most helpful.

#include <iostream>
#include <vector>

using namespace std;

void read(vector<int>& myvector);
void mode(vector<int>& myvector);

int main()
{
    vector<int> myvector;
    read(myvector);
    mode(myvector);

    return 0;
}


void read(vector<int>& myvector){

    int value;
    cout << "Enter a sequence of number space delimited and q to end" << endl;
    while(cin >> value){
        myvector.push_back(value);
    }
    sort(myvector.begin(), myvector.end());
}

void mode(vector<int>& myvector){

    int counter = 1;
    int first, second;
    int num = 0;
    for (int i=1; i<myvector.size(); i++){
    first = myvector.at(i-1);
    second = myvector.at(i);

    if (second == first){
        counter ++;
        num = first;
    }

    else
        first = second;
    }
    cout << "The mode is: " << num << endl;
}

[JewelCpp]

you forgot to reinitialize counter to 1 in else in the for loop in mode

[JasonMcG]

Makes no difference. If I type 3 3 3 6 6 as the sequence it shows the mode as 6 still.

[cire]

Makes no difference.

It makes no difference because it is not enough. You need to keep track of the current run and the longest run.

[keskiverto]

You could consider http://www.cplusplus.com/reference/algorithm/equal_range/